Impact on quality of life caused by vitamin D deficiency in bariatric patients: a literature review

Introduction: Bariatric surgery is a procedure performed to control obesity and its associated morbidities. Surgeries with malabsorptive and mixed techniques cause a deficit in the absorption of micronutrients, including vitamin D. Objective: The objective of this literature review was to investigate studies that verified the impact of vitamin D deficiency on the preand postoperative quality of life of individuals undergoing bariatric surgery. Methods: The search strategy was carried out in the virtual databases PubMed, Scielo, LILACS, Scopus, Web of Science, Embase, and the Virtual Health Library, in addition to gray literature such as Google Scholar, OpenGrey, Ibict/BDTD (Brazilian digital library of theses and dissertations) and ProQuest using the Medical Subject Headings (MeSH) and Health Sciences Descriptors (DeCS) descriptors with Boolean logical operators (AND, OR and NOT. The studies considered potentially eligible were those that presented in the same article the levels of vitamin D in the pre and postoperative period of the individuals, as well as the effect generated on their quality of life from where the data collection and analysis of the main outcomes found were made. Results: The online search resulted in 197 studies located in the virtual bibliographic databases and 115 in the gray literature. After removing the duplicates, 235 articles remained that were read by title and abstract, and 12 articles were chosen for reading the full text, leaving 7 that met the inclusion criteria. In most of the included studies, vitamin D deficiency was higher preoperatively than postoperatively in bariatric individuals. Better levels of 25(OH)D were correlated with reduced body weight, decreased BMI, and improved glycemic profile. Conclusion: Combating obesity remains an important issue in Public Health, with bariatric surgery being a safe way to reduce overweight since vitamin D levels are lower in the postoperative period of bariatric individuals, however, it is suggested to choose the appropriate technique to maintain ideal vitamin indices.